UV rays you must know before buying sunglasses.

[Tabitha Glasses]

Ultraviolet (UV) rays are located just past the violet portion of the visible light spectrum; sunlight is the main source. UV light is broken into three different types: UVC, UVA, and UVB.

1. UVC rays do not reach the Earth because its atmosphere blocks them.

2. UVA has longer wavelengths and passes through glass easily; experts disagree about whether or not UVA damages the eyes.

3. UVB rays are the most dangerous, making sunglasses and sunscreen a must; they don't go through glass.

That is to say UVB is very harmful to our eyeglasses, we should buy and wear sunglasses to prevent Ultraviolet (UV) rays.